Expression of 4E-BP1 and phospho-4E-BP1 correlates with the prognosis of patients with clear cell renal carcinoma

Feng Li,1,2,* Qingshui Wang,3,* Xiaoxue Xiong,3 Chenyi Wang,3 Xiaohua Liu,4 Ziqiang Liao,3 Ke Li,3 Bifeng Xie,5 Yao Lin3 1Department of Pathology, Provincial Clinical Medical College, Fujian Medical University, Fuzhou, Fujian Province, People’s Republic of China; 2Department of Pathology, Fujian Provincial Hospital, Fuzhou, Fujian Province, People’s Republic of China; 3Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou, Fujian Province, People’s Republic of China; 4Department of Obstetrics, Anxi County Hospital, Anxi, Fujian Province, People’s Republic of China; 5College of Life Sciences, Fujian Normal University, Fuzhou, Fujian Province, People’s Republic of China *These authors contributed equally to this work Background: Eukaryotic translation initiation factor 4E (eIF4E) is a key regulator of protein synthesis. Changes in eIF4E activity disproportionally affect the translation of a subset of oncogenic mRNAs in some cancers. Materials and methods: We have assessed the expression levels of vascular endothelial growth factor C (VEGFC), eIF4E, eIF4E-binding proteins (4E-BPs) and phospho-4E-BP1 in clear cell renal carcinoma (ccRCC; n=101) using immunohistochemistry and analyzed the relevant mRNA levels and survival using online databases. Results: The protein levels of VEGFC, an eIF4E-regulated gene, were upregulated in ccRCC tissues compared with adjacent normal renal tissues, indicating an enhanced eIF4E activity in ccRCC. The expression of eIF4E had no significant changes in ccRCC tissues. However, 4E-BP1 and phospho-4E-BP1 were found to be overexpressed in ccRCC tissues (P